<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <title>登录1</title>
  <style>
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }

    /* 动态背景 */
    @keyframes move {
      100% {
        transform: translate3d(0, 0, 1px) rotate(360deg);
      }
    }

    .background {
      position: fixed;
      width: 100vw;
      height: 100vh;
      top: 0;
      left: 0;
      background: #3E1E68;
      overflow: hidden;
    }

    .background span {
      width: 20vmin;
      height: 20vmin;
      border-radius: 20vmin;
      backface-visibility: hidden;
      position: absolute;
      animation: move;
      animation-duration: 45s;
      animation-timing-function: linear;
      animation-iteration-count: infinite;
    }


    .background span:nth-child(0) {
      color: #FFACAC;
      top: 90%;
      left: 47%;
      animation-duration: 8s;
      animation-delay: -17s;
      transform-origin: 2vw 17vh;
      box-shadow: -40vmin 0 5.494502440636581vmin currentColor;
    }

    .background span:nth-child(1) {
      color: #FFACAC;
      top: 31%;
      left: 5%;
      animation-duration: 40s;
      animation-delay: -14s;
      transform-origin: -5vw -14vh;
      box-shadow: -40vmin 0 5.192195104974926vmin currentColor;
    }

    .background span:nth-child(2) {
      color: #FFACAC;
      top: 18%;
      left: 62%;
      animation-duration: 20s;
      animation-delay: -5s;
      transform-origin: -18vw -12vh;
      box-shadow: 40vmin 0 5.72205756381233vmin currentColor;
    }

    .background span:nth-child(3) {
      color: #FFACAC;
      top: 71%;
      left: 45%;
      animation-duration: 30s;
      animation-delay: -2s;
      transform-origin: -4vw -20vh;
      box-shadow: -40vmin 0 5.303503038071778vmin currentColor;
    }

    .background span:nth-child(4) {
      color: #E45A84;
      top: 90%;
      left: 38%;
      animation-duration: 15s;
      animation-delay: -48s;
      transform-origin: 7vw -9vh;
      box-shadow: -40vmin 0 5.882238754040052vmin currentColor;
    }

    .background span:nth-child(5) {
      color: #583C87;
      top: 34%;
      left: 32%;
      animation-duration: 30s;
      animation-delay: -36s;
      transform-origin: -6vw -15vh;
      box-shadow: 40vmin 0 5.183333217256063vmin currentColor;
    }

    .background span:nth-child(6) {
      color: #583C87;
      top: 25%;
      left: 41%;
      animation-duration: 21s;
      animation-delay: -47s;
      transform-origin: -10vw -5vh;
      box-shadow: 40vmin 0 5.345257098222438vmin currentColor;
    }

    .background span:nth-child(7) {
      color: #E45A84;
      top: 16%;
      left: 39%;
      animation-duration: 30s;
      animation-delay: -33s;
      transform-origin: -15vw 3vh;
      box-shadow: -40vmin 0 5.693872337330205vmin currentColor;
    }

    .background span:nth-child(8) {
      color: #583C87;
      top: 42%;
      left: 55%;
      animation-duration: 46s;
      animation-delay: -50s;
      transform-origin: -6vw 25vh;
      box-shadow: 40vmin 0 5.588315610213253vmin currentColor;
    }

    .background span:nth-child(9) {
      color: #E45A84;
      top: 78%;
      left: 25%;
      animation-duration: 44s;
      animation-delay: -21s;
      transform-origin: -4vw -12vh;
      box-shadow: -40vmin 0 5.82170170819547vmin currentColor;
    }

    .background span:nth-child(10) {
      color: #E45A84;
      top: 73%;
      left: 77%;
      animation-duration: 41s;
      animation-delay: -40s;
      transform-origin: 21vw -11vh;
      box-shadow: -40vmin 0 5.838449416658446vmin currentColor;
    }

    .background span:nth-child(11) {
      color: #E45A84;
      top: 48%;
      left: 81%;
      animation-duration: 33s;
      animation-delay: -42s;
      transform-origin: 6vw 19vh;
      box-shadow: 40vmin 0 5.848850560573668vmin currentColor;
    }

    .background span:nth-child(12) {
      color: #E45A84;
      top: 77%;
      left: 7%;
      animation-duration: 25s;
      animation-delay: -1s;
      transform-origin: 15vw 24vh;
      box-shadow: -40vmin 0 5.800039290361969vmin currentColor;
    }

    .background span:nth-child(13) {
      color: #E45A84;
      top: 77%;
      left: 38%;
      animation-duration: 51s;
      animation-delay: -40s;
      transform-origin: -1vw -13vh;
      box-shadow: -40vmin 0 5.876822672246133vmin currentColor;
    }

    .background span:nth-child(14) {
      color: #583C87;
      top: 58%;
      left: 98%;
      animation-duration: 7s;
      animation-delay: -1s;
      transform-origin: -19vw -20vh;
      box-shadow: -40vmin 0 5.622075629639948vmin currentColor;
    }

    .background span:nth-child(15) {
      color: #583C87;
      top: 79%;
      left: 31%;
      animation-duration: 39s;
      animation-delay: -46s;
      transform-origin: 14vw 21vh;
      box-shadow: 40vmin 0 5.022352355698978vmin currentColor;
    }

    .background span:nth-child(16) {
      color: #E45A84;
      top: 41%;
      left: 74%;
      animation-duration: 37s;
      animation-delay: -4s;
      transform-origin: -19vw 3vh;
      box-shadow: 40vmin 0 5.049960684696969vmin currentColor;
    }

    .background span:nth-child(17) {
      color: #583C87;
      top: 56%;
      left: 34%;
      animation-duration: 26s;
      animation-delay: -35s;
      transform-origin: -16vw -7vh;
      box-shadow: -40vmin 0 5.11253385954465vmin currentColor;
    }

    .background span:nth-child(18) {
      color: #583C87;
      top: 84%;
      left: 2%;
      animation-duration: 14s;
      animation-delay: -39s;
      transform-origin: -10vw -6vh;
      box-shadow: 40vmin 0 5.903761483531039vmin currentColor;
    }

    .background span:nth-child(19) {
      color: #E45A84;
      top: 61%;
      left: 39%;
      animation-duration: 21s;
      animation-delay: -36s;
      transform-origin: 14vw 9vh;
      box-shadow: 40vmin 0 5.448311817969409vmin currentColor;
    }

    .background span:nth-child(20) {
      color: #E45A84;
      top: 33%;
      left: 5%;
      animation-duration: 8s;
      animation-delay: -7s;
      transform-origin: 4vw 2vh;
      box-shadow: 40vmin 0 5.013421190075091vmin currentColor;
    }

    /* 动态背景 */

    body {
      height: 100vh;
      background-color: aquamarine;
    }

    .Box {
      position: fixed;
      top: 50%;
      left: 50%;
      transform: translate(-50%, -50%);
      width: 320px;
      background-color: rgba(0, 0, 0, 0.24);
      border-radius: 6px;
      padding: 20px 32px;
    }

    h3 {
      font-size: 22px;
      color: #fff;
      text-align: center;
      margin-bottom: 40px;
      font-weight: 500;
      letter-spacing: 5px;
    }

    input {
      width: 100%;
      height: 35px;
      border: 1px solid #fff;
      background-color: transparent;
      padding-left: 10px;
      font-size: 12px;
      color: #fff;
      margin-bottom: 20px;
      outline: none;
      border-radius: 5px;
    }

    input::placeholder {
      color: #fff;
    }

    .yzmBox {
      display: flex;
      justify-content: flex-start;
    }

    .yzmBox input {
      width: 70%;
      border-top-right-radius: 0;
      border-bottom-right-radius: 0;
    }

    .yzmBox .btn {
      cursor: pointer;
      width: 29%;
      background-color: #aa55ff;
      color: #d8d8d8;
      height: 35px;
      outline: none;
      border: 1px solid #aa55ff;
      font-size: 12px;
      border-radius: 6px;
      margin-left: 1%;
      border-top-left-radius: 0;
      border-bottom-left-radius: 0;
    }

    .forgetPwd {
      text-align: end;
      font-size: 12px;
      color: #ffffff;
      padding-right: 5px;
    }

    .loginBtn {
      width: 100%;
      line-height: 36px;
      text-align: center;
      font-size: 15px;
      color: #fff;
      border-radius: 6px;
      background: linear-gradient(to right, #aa55ff, #E45A84);
      outline: none;
      border: none;
      margin-top: 30px;
    }

    .no {
      margin-top: 30px;
      text-align: center;
      font-size: 12px;
      color: #ffffff;
    }
  </style>
</head>
<body>
<!-- 背景 -->
<div class="background">
  <span></span>
  <span></span>
  <span></span>
  <span></span>
  <span></span>
  <span></span>
  <span></span>
  <span></span>
  <span></span>
  <span></span>
  <span></span>
  <span></span>
  <span></span>
  <span></span>
  <span></span>
  <span></span>
  <span></span>
  <span></span>
  <span></span>
  <span></span>
  <span></span>
</div>

<div class="Box">
  <h3>某某管理系统</h3>
  <form action="">
    <input type="text" placeholder="请输入账号" required>
    <input type="password" placeholder="请输入密码" required>
    <div class="yzmBox">
      <input type="text" placeholder="请输入验证码">
      <button class="btn">发送</button>
    </div>
    <p class="forgetPwd">忘记密码</p>
    <input type="submit" class="loginBtn" value="登录"></button>
    <p class="no">没有账号？立即注册</p>
  </form>
</div>
</body>
</html>